15-CIS-BETA-CAROTENE FOUND IN THE REACTION-CENTER OF SPINACH PHOTOSYSTEM-II

Solvent extraction at similar to 4 degrees C in complete darkness, and subsequent analysis by high-pressure liquid chromatography (at simila r to 4 degrees C) using an apparatus equipped with a two-dimensional d iode-array detector, spectroscopically identified 15-cis-beta-carotene in the reaction center (RC) of spinach photosystem II (PS II), The re sult revises a previous conclusion that beta-carotene bound to the PS II RC takes the all-trans configuration [Fujiwara, H., Hayashi, H., Ta sumi, M., Kanaji, M., Koyama, Y. and Satoh, K. (1987) Chem. Lett, 2005 -2008], and generalizes the concept established for purple photosynthe tic bacteria that 15-cis-carotenoid is naturally selected by the photo synthetic reaction centers.